剑指offer-树

来源：互联网发布：网络女神思瑞在哪直播编辑：程序博客网时间：2024/06/15 15:05
#include<iostream>#include<algorithm>#include<queue>#include<stack>using namespace std;struct BinaryTreeNode{    int data;    BinaryTreeNode *left;    BinaryTreeNode *right;};BinaryTreeNode *InsertNode(BinaryTreeNode *left, BinaryTreeNode *right, int data){    BinaryTreeNode *root=new BinaryTreeNode;    root->left=left;    root->right=right;    root->data=data;    return root;}//按层次打印二叉树   递归和非递归版本void  printByLevel(BinaryTreeNode *root){    queue<BinaryTreeNode *>  q;    q.push(root);    int i=1;    while (!q.empty())    {        BinaryTreeNode *p = q.front();        q.pop();        cout <<i++<< " "<<p->data << endl;        if (p->left)            q.push(p->left);        if (p->right)            q.push(p->right);    }}void  printByLevelTraverse(BinaryTreeNode *root,int i){    cout << i << ":" << root->data << endl;    if (root->left)        printByLevelTraverse(root->left,2*i);    if (root->right)        printByLevelTraverse(root->right,2*i+1);}//先序遍历void PreOrder(BinaryTreeNode *root){    if (root)    {        cout << root->data << " ";        PreOrder(root->left);        PreOrder(root->right);    }}void PreOrderTraverse(BinaryTreeNode *root){   stack<BinaryTreeNode *> s;    BinaryTreeNode *p=root;    while (p||!s.empty())    {        while (p)        {            cout << p->data << " ";            s.push(p);            p=p->left;        }        if (!s.empty()){            p = s.top();            s.pop();            p=p->right;        }    }    cout<<endl;}//中序遍历void MidOrder(BinaryTreeNode *root){    if (root){        MidOrder(root->left);        cout << root->data << " ";        MidOrder(root->right);    }}//递归中序遍历void MidOrderTraverse(BinaryTreeNode *root){    stack<BinaryTreeNode *> s;    BinaryTreeNode *p=root;    while (p||!s.empty())    {        while (p)        {            s.push(p);            p=p->left;        }        if (!s.empty()){            p = s.top();            s.pop();            cout << p->data << " ";            p=p->right;        }    }    cout<<endl;}//后序遍历void PostOrder(BinaryTreeNode *root){    if (root){        PostOrder(root->left);        PostOrder(root->right);        cout << root->data << " ";    }}void PostOrderTraverse(BinaryTreeNode *root){    BinaryTreeNode *p=root;    BinaryTreeNode *q=NULL;    stack<BinaryTreeNode *>  s;    while (p||!s.empty())    {        while (p)        {            s.push(p);            p=p->left;        }        if (!s.empty()){            p = s.top();            if (p->right == NULL||p->right==q){                cout << p->data << " ";                q=p;                p=NULL;                s.pop();            }            else{                p=p->right;            }        }    }    cout<<endl;}//二叉树的深度int DepthOfBinaryTree(BinaryTreeNode *root){    if (root==NULL)                return 0;    int l=DepthOfBinaryTree(root->left);    int r=DepthOfBinaryTree(root->right);    return l>r?l+1:r+1;}//根据前序遍历和中序遍历重建二叉树BinaryTreeNode *ConstructCore(int *startPreOrder, int *endPreOrder, int *startMidOrder, int *endMideOrder){    int rootValue = startPreOrder[0];    BinaryTreeNode *root = new BinaryTreeNode();    root->data=rootValue;    root->left=NULL;    root->right=NULL;    //递归结束条件    if (startPreOrder == endPreOrder){        if (startMidOrder==endMideOrder&&startPreOrder==startMidOrder)                return root;        else            throw exception("inValid input");    }    //在中序遍历中找到根结点的值    int *rootInOrder=startMidOrder;    while (rootInOrder<=endMideOrder&&*rootInOrder!=rootValue)    {            ++rootInOrder;    }    int leftLength=rootInOrder-startMidOrder;    int *leftPreOrderEnd=startPreOrder+leftLength;    if (leftLength > 0){        //构建左子树        root->left = ConstructCore(startPreOrder+1,leftPreOrderEnd,startMidOrder,rootInOrder-1);    }    if (leftLength < endPreOrder - startMidOrder){        //构建右子树        root->right = ConstructCore(leftPreOrderEnd+1,endPreOrder,rootInOrder+1,endMideOrder);    }    return root;}BinaryTreeNode *Construct(int *preOrder, int *midOrder,int n){    if (preOrder==NULL||midOrder==NULL||n<=0)            return NULL;    return ConstructCore(preOrder,preOrder+n-1,                        midOrder,midOrder+n-1);}//打印二叉树中和为某一值的路径void  PrintTreePathOfTarget(BinaryTreeNode *root, int sum, int target, vector<int> &pathVec){    sum+=root->data;    pathVec.push_back(root->data);    bool isLeaf = root->left == NULL&& root->right == NULL;    if (sum == target&&isLeaf)    {        for (auto c:pathVec)            cout << c << " ";        cout<<endl;    }    if (root->left){        PrintTreePathOfTarget(root->left,sum,target,pathVec);    }    if (root->right)    {        PrintTreePathOfTarget(root->right,sum,target,pathVec);    }    pathVec.pop_back();}//二叉树的镜像void MirrorOfTree(BinaryTreeNode *root){    if (root==NULL)  return ;    if (root->left==NULL&&root->right==NULL)                return;    BinaryTreeNode *p = root->left;    root->left = root->right;    root->right = p;    if (root->left)         MirrorOfTree(root->left);    if (root->right)        MirrorOfTree(root->right);}//输入两颗二叉树A和B，判断B是不是A的子结构bool isSubCore(BinaryTreeNode *A, BinaryTreeNode *B){    if (A != NULL&&B != NULL){        if (A->data == B->data){            return isSubCore(A->left,B->left)&&isSubCore(A->right,B->right);        }    }    if (A==NULL&&B==NULL)    return true;    return false;}bool isSubTree(BinaryTreeNode *A, BinaryTreeNode *B){    bool result=false;    if (A->data==B->data)        result = isSubCore(A,B);    if (!result){        result = isSubTree(A->left,B);    }    if (!result){        result = isSubTree(A->right,B);    }}int main(){    //1.创建二叉树    BinaryTreeNode *n1 = InsertNode(NULL,NULL,1);    BinaryTreeNode *n2 = InsertNode(NULL,NULL,7);    BinaryTreeNode *n3 = InsertNode(NULL, NULL, 8);    BinaryTreeNode *n4 = InsertNode(NULL, NULL, 3);    BinaryTreeNode *n5 = InsertNode(n1, n2, 4);    BinaryTreeNode *n6 = InsertNode(n3, n4, 5);    BinaryTreeNode *root = InsertNode(n5,n6,2);    //2.按层次打印二叉树    printByLevel(root);     //迭代    printByLevelTraverse(root,1);//递归    //3.先序遍历    PreOrder(root);cout<<endl;    PreOrderTraverse(root);    //4.中序遍历    MidOrder(root);cout<<endl;    MidOrderTraverse(root);    //5.后序遍历    PostOrder(root);cout<<endl;    PostOrderTraverse(root);    //6.返回二叉树的深度    cout << DepthOfBinaryTree(root)<<endl;    //7.根据前序遍历和中序遍历重建二叉树    //const int n=7;    //int  preOrder[n] = {2,4,1,7,5,8,3};//已知前序遍历    //int  midOrder[n] = {1,4,7,2,8,5,3};//已知中序遍历    //Construct(preOrder,midOrder,n);    //8.打印和为某一值的路径    vector<int>  pathVec;    PrintTreePathOfTarget(root,0,15,pathVec);    //9.二叉树的镜像//    MirrorOfTree(root);//    printByLevel(root);    //10.输入两颗二叉树A和B，判断B是不是A的子结构    BinaryTreeNode *A=root;    BinaryTreeNode *B=n5;    bool flag= isSubTree(A,B);    cout<<flag<<endl;    system("pause");    return 0;}
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